Unable to update Macfee Total Protection

We have purchesed macfee total protection before one month , from that it showing different problems and fail to update. We Windows Xpnull installed on all our machines. Errot masseges something like this :

1. Unbale to connect macfee total protection server

2. Internet connection not available I have checked with browser setting and registry setting.We can reach to macfee site with IP address , but not with domain name.What should be the problem ?Please Help.Thanking U.